OTHER PRODUCTION PROCESSES

In order to increase copperas processing, a ferrous sulphate monohydrate (trade name Monosal) milling and packing line was installed in 1994, which is periodically expanding. Here, dehydrated copperas taken from the iron red pigments line is processed for granulometry inaccordance to customer demands and subsequently dispatched in big bags, in bags on palettes or in road-transport tanks. The current capacity of the line is about 13,000 tonnes per year. During 2006 the amount of Monosal produced was 12,766 tonnes.

Along with ilmenite, sulphuric acid is the second basic raw material used in titanium dioxide manufacture. It is manufactured at PRECHEZA a.s. from liquid sulphur in the S-1 sulphuric acid plant. This unit began production in 1962 with an annual capacity of 1000,000 tonnes of acid. Extensive reconstruction was carried out in 1989 and 2001 resulting in an increased annual capacity for 140,000 tonnes. Approximately 90% of sulphuric acid production is used during the manufacture of titanium dioxide, the surplus material being sold.

Waste water with a notable content of sulphuric acid and copperas are by-products of titanium dioxide production. Copperas is processed partly into iron pigments and ferrous sulphate monohydrate, while the remainder is sold, KEMIFLOC a.s. being the biggest customer. Copperas production was reduced by the processing of ilmenite with a lower iron content, and with this, (together with the increased copperas processing capacity at PRECHEZA), its comprehensive utilisation is assured, even during increased titanium dioxide production.
Copperas previously stored on dump sites is being processed into ferric coagulants by the sister-company KEMIFLOC a.s. Přerov.

Waste sulphuric acid is reprocessed on a neutralising line in two stages. The first stage initiates the neutralisation of free sulphuric acid using limestone, the second  promotes neutralisation of the remaining sulphur using lime. Of the resultant materials, white gypsum PREGIPS is used in the manufacture of cement or plaster in the construction industry, while the brown PRESTAB is used as a granular additive for technical recultivation.